This invention relates to an antiperspirant composition in the form of a stick. More particularly, it concerns an antiperspirant composition in the form of a stick in which the antiperspirant material is distributed substantially homogeneously throughout the stick.
It is well known in the prior art to prepare stick antiperspirant compositions. These, in general, are prepared by forming a liquid melt of a waxy base, incorporating the antiperspirant material e.g. aluminum chlorhydroxide in the liquid melt, pouring the liquid melt containing the antiperspirant material into a mold and allowing the melt to cool and solidify. Processes of this character are described in U.S. Pat. No. 4,049,792 and "Cosmetics Science and Technology" edited by Edward Sagarin, Interscience Publishers, Inc. New York, 1957 p. 730.
It has been found, however, that when these sticks are prepared in accordance with the prior art methods, the antiperspirant material was not uniformly distributed throughout the stick. The antiperspirant material tended to settle towards the bottom of the stick, so that the concentration of the antiperspirant material in the upper 1/4 of the stick was significantly less than that found in the rest of the stick. This is obviously a disadvantage since during the early use of the stick, insufficient active material may be delivered per application; whereas, in the later use of the stick more active material may be deposited than is required.